/* style.css */
:root {
  --primary-color: #38BDF8;
  --primary-hover: #A5F3FC;
  --bg-color: #05070D;
  --text-color: #E8F0FF;
  --text-light: #94a3b8;
  --card-bg: rgba(255, 255, 255, 0.06);
  --border-color: rgba(165, 243, 252, 0.3);
  --header-h: 70px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text-color);
  background-color: #05070D;
  /* 静态电路细网格打底，与深色渐变底色合并 */
  background-image: 
    linear-gradient(rgba(56, 189, 248, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(56, 189, 248, 0.05) 1px, transparent 1px),
    linear-gradient(to bottom, #05070D, #070D18);
  background-size: 64px 64px, 64px 64px, 100% 100%;
  background-attachment: fixed;
  line-height: 1.6;
  min-height: 100vh;
}

a {
  text-decoration: none;
  color: inherit;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* P0: 锚点防遮挡 */
section[id] {
  scroll-margin-top: 80px;
}

/* P2: 跳转到主要内容 */
.skip-to-content {
  position: absolute;
  top: -100px;
  left: 20px;
  background: var(--primary-color);
  color: #05070D;
  padding: 10px 20px;
  border-radius: 0 0 6px 6px;
  font-weight: 700;
  z-index: 9999;
  transition: top 0.2s;
}
.skip-to-content:focus {
  top: 0;
}

/* P2: 全局可见焦点样式 */
a:focus-visible,
button:focus-visible,
details summary:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 3px;
  border-radius: 4px;
}

/* FAQ: details/summary 样式（外观与原 faq-item 一致） */
.faq-item {
  background: var(--card-bg);
  margin-bottom: 15px;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  backdrop-filter: blur(8px);
  overflow: hidden;
}
details.faq-item summary {
  font-size: 16px;
  font-weight: 600;
  padding: 20px;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--primary-color);
}
details.faq-item summary::-webkit-details-marker { display: none; }
details.faq-item summary::after {
  content: '+';
  font-size: 22px;
  color: var(--primary-color);
  flex-shrink: 0;
  transition: transform 0.2s;
}
details.faq-item[open] summary::after {
  transform: rotate(45deg);
}
details.faq-item .faq-answer {
  padding: 0 20px 20px;
  color: var(--text-light);
  line-height: 1.7;
}


header {
  background: rgba(5, 7, 13, 0.8);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 5px rgba(56, 189, 248, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid rgba(56, 189, 248, 0.1);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.logo {
  font-size: 24px;
  font-weight: bold;
}

.logo a {
  color: var(--primary-color);
  text-shadow: 0 0 10px rgba(56, 189, 248, 0.6);
}

.main-nav {
  display: flex;
  gap: 25px;
}

.main-nav a {
  font-weight: 500;
  color: var(--text-color);
  transition: color 0.3s, text-shadow 0.3s;
}

.main-nav a:hover {
  color: var(--primary-color);
  text-shadow: 0 0 8px rgba(56, 189, 248, 0.4);
}

.btn {
  display: inline-block;
  background-color: var(--primary-color);
  color: #05070D;
  padding: 12px 24px;
  border-radius: 6px;
  font-weight: 600;
  text-align: center;
  transition: all 0.3s;
  box-shadow: 0 0 15px rgba(56, 189, 248, 0.3);
}

.btn:hover {
  background-color: var(--primary-hover);
  color: #05070D;
  box-shadow: 0 0 25px rgba(165, 243, 252, 0.6);
}

.hero {
  text-align: center;
  padding: 80px 20px;
  background: transparent;
}

.hero h1 {
  font-size: 42px;
  margin-bottom: 20px;
  color: var(--text-color);
  text-shadow: 0 0 15px rgba(56, 189, 248, 0.6);
}

.hero p {
  font-size: 18px;
  color: var(--text-light);
  margin-bottom: 30px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.section-title {
  text-align: center;
  font-size: 32px;
  margin: 60px 0 40px;
  text-shadow: 0 0 12px rgba(56, 189, 248, 0.5);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 30px;
}

.card {
  background: var(--card-bg);
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.2);
  border: 1px solid var(--border-color);
  text-align: center;
  backdrop-filter: blur(8px);
}

.card h3 {
  margin: 15px 0;
  font-size: 20px;
  color: var(--primary-color);
}

.card p {
  color: var(--text-light);
}

.pricing-card {
  display: flex;
  flex-direction: column;
}

.pricing-card .price {
  font-size: 36px;
  font-weight: bold;
  color: var(--primary-color);
  margin: 20px 0;
  text-shadow: 0 0 10px rgba(56, 189, 248, 0.3);
}

.pricing-card ul {
  list-style: none;
  margin-bottom: 30px;
  text-align: left;
}

.pricing-card ul li {
  margin-bottom: 10px;
  color: var(--text-light);
}

.pricing-card ul li::before {
  content: "✓ ";
  color: var(--primary-color);
  font-weight: bold;
  text-shadow: 0 0 5px rgba(56, 189, 248, 0.5);
}

.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--card-bg);
  margin-bottom: 15px;
  padding: 20px;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  backdrop-filter: blur(8px);
}

.faq-item h4 {
  font-size: 18px;
  margin-bottom: 10px;
  color: var(--primary-color);
}

.faq-item p {
  color: var(--text-light);
}

footer {
  background: #03050a;
  color: var(--text-light);
  padding: 40px 20px;
  margin-top: 80px;
  text-align: center;
  border-top: 1px solid rgba(56, 189, 248, 0.1);
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-bottom: 20px;
}

.footer-links a:hover {
  color: var(--primary-color);
}

.sub-page {
  padding: 60px 20px;
  max-width: 800px;
  margin: 0 auto;
  background: var(--card-bg);
  margin-top: 40px;
  margin-bottom: 40px;
  border-radius: 12px;
  box-shadow: 0 2px 20px rgba(0,0,0,0.3);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(8px);
}

.sub-page ul {
  padding-left: 20px;
  margin-bottom: 15px;
}

.sub-page ul li {
  margin-bottom: 8px;
  color: var(--text-light);
}

.sub-page h1 {
  margin-bottom: 30px;
  border-bottom: 2px solid rgba(56, 189, 248, 0.2);
  padding-bottom: 10px;
  text-shadow: 0 0 10px rgba(56, 189, 248, 0.4);
}

.sub-page h2 {
  margin-top: 25px;
  margin-bottom: 15px;
  color: var(--primary-color);
}

.sub-page p {
  margin-bottom: 15px;
  color: var(--text-light);
}

/* =========================================
   动效独立图层 (Background Decoration)
   ========================================= */
.bg-decoration {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -10;
  pointer-events: none;
  overflow: hidden;
}

/* 1. 扫描光带 */
.scan-line {
  position: absolute;
  top: -90px;
  left: 0;
  width: 100%;
  height: 90px;
  background: linear-gradient(to bottom, transparent, rgba(56, 189, 248, 0.1) 80%, rgba(56, 189, 248, 0.4));
  animation: scan 7s linear infinite;
}

@keyframes scan {
  0% { transform: translateY(0); }
  100% { transform: translateY(calc(100vh + 90px)); }
}

/* 2. 右上三圈同心脉冲环 */
.pulse-ring {
  position: absolute;
  top: 10%;
  right: 15%;
  width: 150px;
  height: 150px;
  margin-top: -75px;
  margin-right: -75px;
  border: 1px solid rgba(56, 189, 248, 0.6);
  border-radius: 50%;
  opacity: 0;
  animation: pulse 3.9s ease-out infinite;
}
.pulse-1 { animation-delay: 0s; }
.pulse-2 { animation-delay: 1.3s; }
.pulse-3 { animation-delay: 2.6s; }

@keyframes pulse {
  0% { transform: scale(0.5); opacity: 0.8; }
  100% { transform: scale(3.5); opacity: 0; }
}

/* 3. 左上青色呼吸光晕 */
.glow-orb {
  position: absolute;
  top: 15%;
  left: 10%;
  width: 300px;
  height: 300px;
  margin-top: -150px;
  margin-left: -150px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.15), transparent 70%);
  animation: breathe 9s ease-in-out infinite;
  border-radius: 50%;
}

@keyframes breathe {
  0%, 100% { transform: scale(1); opacity: 0.3; }
  50% { transform: scale(1.4); opacity: 0.8; }
}

/* prefers-reduced-motion 降级处理 */
@media (prefers-reduced-motion: reduce) {
  .scan-line, .pulse-ring, .glow-orb {
    animation: none;
    opacity: 0;
  }
  .glow-orb {
    opacity: 0.3; /* 保留微弱的静态光晕 */
  }
}

/* =========================================
   响应式断点 (不变)
   ========================================= */
@media (max-width: 768px) {
  .grid-3, .grid-2 {
    grid-template-columns: 1fr;
  }
  .hero h1 {
    font-size: 32px;
  }
  .header-inner {
    flex-direction: column;
    justify-content: center;
    height: auto;
    padding: 15px 0;
    gap: 15px;
  }
  .main-nav {
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
  }
  .btn {
    width: 100%;
    padding: 15px;
    font-size: 18px;
  }
  .footer-links {
    flex-wrap: wrap;
    gap: 15px;
  }
}